A haiku is a brief Japanese form that has been adapted into English in various ways. Its usual definition is that it is a three-line poem, consisting of seventeen syllables split 5 - 7 - 5. Other criteria (such as a 'zen mood', a reference to a season, or the poem being divided by a word that implies some form of cutting) may be demanded, and may even replace the strict syllable count. John Stallworthy considers Ezra Pound's 'In a Station of the Metro' a haiku, as, although it has only two lines and considerably more than 17 syllables, it has the brief and direct presentation of an image that many haiku have.
Peter Goldsworthy's 'Razor' is arguably a haiku, despite its syllables breaking 5-6-6; it has the direct presentation of an image in seventeen syllables and three lines, with a light caesura. 'Strugnell's Haiku', a comic take on the form by Wendy Cope, sets up the humour by "combin[ing] the feeling of Japanese Haiku with the banality of poor old Strugnell"; it's worth noticing that the syllable count, the reference to a season, and (in two out of three cases) a caesura to cut the haiku in two are present. 'Strugnell' may not have any profound insights, but he knows his formal rules.